Spark-plug.



A. n. PRTER.

SPARK PLUG.

APPLICATION FILED MAA. 2a. 1917.

Patented Aug, 20, 191s. i i* lu/vanto@ PRTEE, QF SGBERVELLE, NEVI JEBiSE-"',

E Wlf, F SQUIER/VILLE, NEE" JERSEY.

il. illlll .liipliceten Marcil "n il' et l, lrrHUn D. Powell,

lle jlonlerville, in the county et' Somerset and Stilte of New Jersey llave invented certain new Plugs, ot Winch tile following is a specificaltion.

lllle lili elllloll le Ll ee to Lin Lnploi co :perl: ping und lille le its prinmry object to lerende ll device of 'this ciinrucl'er haring tiro distinct spark gane so tllllt two distinct ellas will be forllled eacll time current is lllseed tllrongzll ille ping.

r"l :is :l 'further object to le invention ilus 'ide u spark plug' inning; e lullin elecone. :l ground electrode,.lmd ll neutrul elecooe interposed lletrfccn the seid tiret lnen honed electrodes so that current iowing ill lluggll tile -lnuin electrode 'will tiret lle Calwell 'lo jump from tlle malin electrode to tlie neutrali electrode lo forni one spark und will tllen 'o sensed to jump from flic neutral eleclfl'ode to tile ground electrode lo form spark. l the inl'ention llas is il still urtllcr to provide :l spark plug n'llicll ill lle of Simple eonstrnction and which may be employed in connection with substantially any conventional type ol internal combustion engine.

miller and incidental objects; will appear `e proceeds eno in tile drawe wherein l llllre illustrated tile preferred embodiment of tile invention und Wllcrei similar reerenee characters designate correslonding parts throughout tile several Views:

is a eleretion of lng:r imiii?, is .Sectional View more particuM ly herring the construction of tile plug end ine mounting of tlle electrodes thereon,

F is leotloln pien vie-W particularly eilorqing tile disposition of elle electrodes et zope therebetween.

ln eelrjfing out tile invention, my im proved eperll' plug is formed vwith a lne'- tellic sllell l0., the lower extremity of which is screw threaded so tlliit the plug may be 'connected in tile usuel manner 'with an engine cylinder, Removellly iitted through 'tile glieli is porcelain il. The terni porcellini eeee leef?, :le mollet te include any eecienfzon of Lettere Patent.

United States, residing at and useful improvement-s in SpelloA .tile porcelain.

, 2917. Serial No. li

j:li'proved character of insulating materiel formed into a body similar to the porcelain l1. Tile porcelain il is formed intermediate its ends with un annular shoulder l2 e0nitl-(uitingr :i Similar shoulder i3 Within the ellell and interposed betWeen-thesaid shoulders is :i spring packing washer 14'. Screw ilirclldcd into tlle upper extremity of the Snell to surround Llle porcellini il is il nut l5 connecting' tllc Shoulder 12 of tllc porcelain, is ll spring' packing misil-er 1G sinnlll to ille washer le'.

Fitted tllrollgll tile porcelain or energized electrode l?, tlle upper elo l!) with irllicll the nut 18 is arranged to co operate for cmlneetin;7 a circuit Wire, as conventionally illustrated in the drawings, with the Spark plug. (lf course, an ordinary nut may be substituted for the cap if desired. t the inner extremity of the threaded portion of tile electrode, tlle porcelain il is provided with n recess l1 and tlle electrode at tlle Suid recess is reduced as sllown'at 17. The recess isfillec with e suitable cement engaging' in tile reduced portion 17" of tile electrode for connectingl the electrode with lient longitudinally from the cccentricelly its outer end,

porceelectrode 1T is reduced portion il" to project thwlngll tile porcelain and, et extends below tile lowerend of tile luin adjacent one side thereof. Y

Connected to the ellell l below tile lower end of tile porcelain 11 is e ground electrode 20 which projects tangentielly into the ellell from tlle Wall thereof and enllledded in tile lower extremity of the porcelain orotllerwise connected thereto, is :i neuiral electrode 2L the lower extremity of which is provided with a laterally directed arm or terminal 22 arranged as pllrtionlarlv shown in Fig/3, between the electrodes 17 and 20 in Soaced relation thereto. As illustrated in Fig. 2, tile lower extremity of tlle electrode 17 es well as the outer extremities of the electrodes 20 and 21 is housed Within the lower end of the shell 10.

As will now lle observed upon reference to Fig. 3. one spark gap is provided between tile mein electrodes 17 zigld the neutral electrode porcelain Witll the shell' and interposed between ille sind nut and tile' il is moin The lower extremity of tlle f llo 

